The present invention is directed to an ink jet recording head and, in particular, to an on-demand type ink jet recording head in which the dimensions of the components thereof are selected to permit high integration of the components so that the ink jet nozzles may be substantially more closely spaced than had been available in prior art constructions.
It is known to provide an on-demand type ink jet recording head having multiple nozzles which provides a plurality of on-demand type ink jets arranged on a head substrate for ejecting ink particles or droplets through the nozzles under ink pressure converted from electric signals by the action of an electro mechanical transducer such as a piezoelectric element which actuates a vibratory plate. Such prior art constructions are shown in U.S. Pat. Nos. 4,199,769 and 4,216,483. The ink jet assembly of U.S. Pat. No. 4,216,483, for example, requires that the nozzles thereof be angled to permit close spacing of the nozzle openings at the end of the ink jet recording head. Such a construction as well as that shown in U.S. Pat. No. 4,119,769 do not permit high integration of the ink jet head components.
In such prior art constructions, when an increase in the degree of nozzle integration is desired, the length of each nozzle must increase. However, when the nozzle length is increased, various operating characteristics of each nozzle must be increased. Thus, these prior art limitations prevent the design of an ink jet recording head having highly integrated multiple nozzles. Accordingly, it is desired to provide an ink jet recording head in which high nozzle integration may be provided. Through experimentation and theoretical calculation, the present invention provides such a highly integrated nozzle configuration for on-demand type ink jet recording heads.